Patent Yard Sign in
Lapsed, fee not paid

Resonant inverter and isolated resonant power supply device

US 9,812,974 B2 · Assignee: TDK CORPORATION · Inventors: Imai; Katsunori

USPTO PDF

Overview

Drawings on their way

This patent has 8 drawing sheets. They are being downloaded; every one is in the USPTO PDF now.

Open the USPTO PDF

Full text on its way

This patent is listed from its USPTO record because it passed every check. Its abstract, claims and description are being downloaded from USPTO and will appear here within days. Until then, read it in the USPTO PDF or on Google Patents.

Why it's free to use

  • The USPTO Official Gazette of January 6, 2026 lists it as expired on November 7, 2025 for an unpaid maintenance fee.
  • It isn't on any reinstatement notice published since.
  • Its 1 US relative has also lapsed, expired or never issued.
  • We check US rights only. Check foreign counterparts before selling abroad.
FiledMarch 28, 2016
GrantedNovember 7, 2017
Expired (fee)November 7, 2025
Application number15/082753
Classification (CPC)H02M3/33546 +5 more
Length18 pages

Drawings 8

The 8 drawing sheets are on the way. Every sheet is in the USPTO PDF.

Claims

On their way

The claims are being downloaded from USPTO and will appear here within days. Until then, read it in the USPTO PDF or on Google Patents.

Description

On its way

The description is being downloaded from USPTO and will appear here within days. Until then, read it in the USPTO PDF or on Google Patents.

Timeline & family

Timeline From USPTO dates

201720182019202020212022202320242025Application filedMarch 28, 2016Application publishedNov 17, 2016Patent grantedNov 7, 20173.5-year fee paidMay 7, 20217.5-year fee not paidMay 7, 2025Patent expiredNov 7, 2025

Maintenance fees

Fees are due 3.5, 7.5 and 11.5 years after grant. This patent expired on November 7, 2025, so the fee marked "not paid" was the one that went unpaid.

3.5-year feeDue May 7, 2021Paid
7.5-year feeDue May 7, 2025Not paid
11.5-year feeDue May 7, 2029Never came due

US family 2 documents, by filing date

Published applicationUS 2016/0336865 A1

RESONANT INVERTER AND ISOLATED RESONANT POWER SUPPLY DEVICE

Filed Mar 2016 · published Nov 2016
Published application
This documentUS 9,812,974 B2

Resonant inverter and isolated resonant power supply device

Filed Mar 2016 · granted Nov 2017
Lapsed, fee not paid

Earlier publications, parents and continuations. None of them can still be enforced, or this patent would not be listed.

US patents it cites 0

No US citations on record.

Sources & verification

Verification

  • The USPTO Official Gazette of January 6, 2026 lists it as expired on November 7, 2025 for an unpaid maintenance fee.
  • It isn't on any reinstatement notice published since.
  • Its 1 US relative has also lapsed, expired or never issued.
  • Rechecked against USPTO records every day.
  • We check US rights only. Check foreign counterparts before selling abroad.

Confirm it yourself

  1. Open the file history on Patent Center.
  2. The status should read "Patent Expired Due to NonPayment of Maintenance Fees Under 37 CFR 1.362".
  3. Check the documents for any later petition to revive or reinstate.

Everything on this page comes from the documents linked above.

More in Energy & Sustainability

All Energy & Sustainability
Lapsed, fee not paidUS 9,812,977 B2
Energy & Sustainability · US 9,812,977 B2

Resonant converters with an improved voltage regulation range

A method comprises determining an operating mode based upon an input voltage and an output voltage of a resonant converter, wherein the resonant converter comprises a switch network coupled to an input dc power source,…

Filed2015
LapsedNov 2025
OwnerFuturewei Technologies, Inc.